[req] better linebreak management

I thought the “convert linebreak” function in MovableType was terrible, but WP is even worse… everywhere, a bloody nightmare. I had to disable it; now I’m basically forced to use a filter like Markdown, and I don’t want to, or avoid html altogether — just give me an option to choose whether or not the linebreaks conversion is required on a post-by-post basis. This needs serious fixing.